Temperatures plunged into the 20s after sundown in Portland and are expected to keep dropping overnight, the opening salvo in what weather forecasters say will be a dangerous 48 hours of ice and cold. But forecasters express optimism that the region will avoid a repeat of the 2021 ice storm that caused the largest power outage in Oregon history.
The high Wednesday at Portland International Airport was 43 degrees. Update: By Thursday morning, that temperature had dropped by more than 20 degrees.
“Our expectation is that by 10 tonight, it will be in the lower to mid-20s,” says National Weather Service hydrologist Andy Bryant. “By 4 am, it will be around 20 degrees in the metro area. By 10 am tomorrow, it will be in the upper teens. And that’s probably where we’ll bottom out.”
The arrival of an arctic air mass caused Multnomah County to declare a state of emergency and open four severe weather shelters across the city. Locations are listed here.
It will be a dangerously cold night for anyone outdoors. Meteorologists say the wind chill would reach single digits across the city, with East Portland feeling as cold as zero degrees and the Columbia River Gorge experiencing wind chill factors of minus 15.
The frigid conditions are part of a wave of arctic air descending rapidly across the American West, with steep temperature drops being reported in places like Denver and Cheyenne, Wyo.
The temperature is not expected to rise much on Thursday, and an additional danger comes in the form of freezing rain Thursday night, lasting through much of Friday. That raises the specter of ice accumulating on trees and power lines—the phenomenon that blew transformers across Oregon in 2021 and left 330,000 people without electricity.
Portland General Electric told customers to prepare flashlights, a 72-hour supply of ready-to-eat food and water, and car chargers for phones.
But Bryant says a repeat of the 2021 disaster is unlikely. What gave him pause was the high winds coming out of the Gorge.
“I don’t know if we’re going to have enough ice accumulation,” he tells WW. “Tree branches with a little bit of ice accumulation and those winds…I don’t know. Seems like an opportunity for some problems.”
He says to expect the mercury to rise again by Christmas Eve. “Hunker down,” Bryant adds, “and tell ourselves by Saturday morning, it will all be OK.”